U.S. patent application number 11/838304 was filed with the patent office on 2008-11-20 for imaging device, imaging system, and methods of imaging.
This patent application is currently assigned to Novelis, Inc.. Invention is credited to Russell W. Bowden, Tse Chen Fong, John W. Goodnow, Paul A. Magnin, David G. Miller.
Application Number | 20080287801 11/838304 |
Document ID | / |
Family ID | 39082688 |
Filed Date | 2008-11-20 |
United States Patent
Application |
20080287801 |
Kind Code |
A1 |
Magnin; Paul A. ; et
al. |
November 20, 2008 |
IMAGING DEVICE, IMAGING SYSTEM, AND METHODS OF IMAGING
Abstract
An imaging device, imaging system, and methods of imaging are
provided. The imaging device may fit inside a diagnostic or
therapeutic assembly, such as a biopsy, drainage, or other type
therapy needle assembly. The imaging device may reside inside the
diagnostic or therapy assembly as the combined device is advanced
to a desired location. Two-dimensional or three-dimensional
ultrasonic images may be produced that allow for the accurate
placement of the diagnostic or therapy assembly.
Inventors: |
Magnin; Paul A.; (Andover,
MA) ; Fong; Tse Chen; (Calgary, CA) ; Bowden;
Russell W.; (Tyngsboro, MA) ; Goodnow; John W.;
(Arlington, MA) ; Miller; David G.; (Bradford,
MA) |
Correspondence
Address: |
LEYDIG, VOIT & MAYER, LTD
TWO PRUDENTIAL PLAZA, SUITE 4900, 180 N. STETSON
CHICAGO
IL
60601-6731
US
|
Assignee: |
Novelis, Inc.
|
Family ID: |
39082688 |
Appl. No.: |
11/838304 |
Filed: |
August 14, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60837320 |
Aug 14, 2006 |
|
|
|
Current U.S.
Class: |
600/463 |
Current CPC
Class: |
A61B 8/445 20130101;
A61B 8/0841 20130101; A61B 8/4461 20130101; A61B 8/0833 20130101;
A61B 2090/3782 20160201; A61B 8/483 20130101; A61B 8/12 20130101;
A61B 18/1492 20130101 |
Class at
Publication: |
600/463 |
International
Class: |
A61B 8/13 20060101
A61B008/13 |
Claims
1. An imaging device, comprising: a housing; a scanning assembly
configured to output signals and receive return signals to produce
an image when oscillated, wherein the scanning assembly includes an
ultrasonic transducer disposed within the housing at an angle with
respect to a central axis of the imaging device; and an angle
encoder configured to encode a rotational angle of the scanning
assembly.
2. The imaging device of claim 1, wherein the scanning assembly is
disposed at one end of the housing.
3. The imaging device of claim 1, further comprising at least one
grip disposed on an outer surface of the housing.
4. The imaging device of claim 1, wherein the image comprises a
conical forward-looking image.
5. The imaging device of claim 4, wherein the imaging is
representative of tissue on a surface of a cone.
6. The imaging device of claim 4, wherein the image comprises a
forward-looking sector image.
7. The imaging device of claim 4, wherein the image comprises a
3-dimensional volumetric image.
8. The imaging device of claim 1, wherein the imaging device is
configured to be manually rotated.
9. The imaging device of claim 1, wherein the imaging device is
configured to be rotated by a drive mechanism.
10. The imaging device of claim 1, wherein the transducer is
disposed at an angle .gtoreq..about.0.degree. and
.ltoreq..about.90.degree. with respect to the central axis of the
imaging device.
11. The imaging device of claim 1, wherein the transducer is
disposed at an angle .gtoreq..about.10.degree. and
.ltoreq..about.30.degree. with respect to the central axis of the
imaging device.
12. The imaging device of claim 1, wherein the ultrasonic
transducer comprises: a face plate that serves as a matching layer;
a piezoelectric transducer; and an absorptive backing layer that
attenuates sound waves emanating from a rear side of the
piezoelectric transducer.
13. The imaging device of claim 12, wherein the matching layer is
.about.1/4 wavelength thick.
14. A diagnostic or therapeutic assembly comprising the imaging
device of claim 1.
15. The diagnostic or therapeutic assembly of claim 14, wherein the
diagnostic or therapeutic assembly is configured to be advanced or
retracted over the imaging device.
16. An imaging system comprising the imaging device of claim 1.
17. The imaging device of claim 1, wherein a distal end of the
imaging device is sharp.
18. The imaging device of claim 1, wherein a distal end of the
imaging device is blunt.
19. The imaging device of claim 1, further comprising a therapy
device disposed at a distal end of the imaging device.
20. The imaging device of claim 19, wherein the therapy device
comprises an ablation device.
21. The imaging device of claim 20, wherein the ablation device is
oriented at an angle about the central axis of the imaging
device.
22. The imaging device of claim 21, wherein the ablation device is
oriented .about.180.degree. around the central axis of the imaging
device from the transducer.
23. The imaging device of claim 19, wherein the therapy device
includes a drill or reamer.
24. The imaging device of claim 1, further comprising a sector
scanning mechanism configured to rotate the scanning assembly about
the central axis of the imaging device to produce a sector
image.
25. The imaging device of claim 24, wherein the sector scanning
mechanism comprises: a rotatable axle on which the scanning
assembly including the transducer is mounted; and a drive shaft
configured to rotate the axle.
26. The imaging device of claim 25, wherein the sector scanning
mechanism further comprises a gear configured to convert rotation
of the drive shaft into angular displacement of the transducer.
27. The imaging device of claim 25, wherein the sector scanning
mechanism further comprises a slotted encoder wheel configured to
record an angle of the scanning assembly.
28. The imaging device of claim 25, wherein the sector scanning
mechanism further comprises a support mechanism configured to
support the drive shaft within the housing.
29. The imaging device of claim 25, wherein the sector scanning
mechanism further comprises an angle encoder attached to the drive
shaft.
30. The imaging device of claim 29, wherein the angle encoder
comprises a slit wheel and a photo interrupter.
31. The imaging device of claim 24, wherein the sector scanning
mechanism comprises a draw string mechanism configured to rotate
the axle.
32. The imaging device of claim 31, wherein the draw string
mechanism comprises a pulley mounted on a rotatable shaft and a
draw string attached to the pulley and to the scanning
assembly.
33. The imaging device of claim 32, further comprising an angle
encoder attached to the rotatable shaft.
34. The imaging device of claim 24, wherein the sector scanning
mechanism comprises: a tube disposed within the housing; at least
one slit formed in one end of the tube adjacent to the scanning
assembly; and at least one pin provided on the scanning assembly to
mate with the at least one slit.
35. The imaging device of claim 34, wherein the sector scanning
mechanism further comprises a gear provided at another end of the
tube.
36. The imaging device of claim 34, wherein the sector scanning
mechanism further comprises an angle encoder attached to the
tube.
37. The imaging device of claim 24, wherein the sector scanning
mechanism comprises a pull-and-retract mechanism.
38. The imaging device of claim 37, wherein the pull-and-retract
mechanism comprises: a cable or rod attached to the scanning
assembly; a pulley attached to the cable or rod; and a restoring
spring attached to the scanning assembly.
39. The imaging device of claim 1, further comprising a sector
scanning mechanism configured to oscillate the scanning assembly to
scan a sector.
40. The imaging device of claim 39, wherein the sector scanning
mechanism oscillates the scanning assembly in a plane substantially
perpendicular to the central longitudinal axis of the scanning
assembly to produce a sector image.
41. The imaging device of claim 39, wherein the sector scanning
mechanism comprises an oscillating drive shaft mechanism.
42. The imaging device of claim 41, wherein the oscillating drive
shaft mechanism comprises: a input shaft; an input crank attached
to the input shaft; a connecting rod one end of which is attached
to the input shaft; an output crank attached to the other end of
the connecting rod; and an output shaft attached to the output
crank and to the scanning assembly.
43. The imaging device of claim 42, wherein the oscillating drive
shaft mechanism further comprises a drive mechanism attached to the
input shaft.
44. The imaging device of claim 41, further comprising a rotating
mechanism configured to rotate the housing.
45. The imaging device of claim 44, wherein the rotation mechanism
comprises: a first gear mounted on the housing; a second gear
configured to drive the first gear; and a drive shaft attached to
the second gear.
46. The imaging device of claim 45, further comprising a drive
mechanism attached to the drive shaft.
47. The imaging device of claim 46, wherein the drive mechanism is
configured to drive both the rotating mechanism and the sector
scanning mechanism.
48. The imaging device of claim 47, wherein the sector scanning
mechanism comprises a input shaft; an input crank attached to the
input shaft; a connecting rod one end of which is attached to the
input shaft; an output crank attached to the other end of the
connecting rod; and an output shaft attached to the output crank
and to the scanning assembly.
49. The imaging device of claim 48, further comprising a connection
mechanism configured to connect the drive mechanism to the drive
shaft of the rotating mechanism and the input shaft of the sector
scanning mechanism.
50. The imaging device of claim 39, wherein the sector scanning
mechanism comprises an oscillating motor.
51. The imaging device of claim 1, wherein the scanning assembly
comprises at least two transducers mounted thereon.
52. The imaging device of claim 51, wherein the at least two
transducers are each mounted at an angle about the central
longitudinal axis of the scanning assembly.
53. The imaging device of claim 52, wherein the at least two
transducers are mounted at different angles about the central
longitudinal axis of the scanning assembly, such that the scanning
assembly produces at least two images when oscillated.
54. The imaging device of claim 51, wherein the at least two
transducers are mounted at different angle from the central axis of
the imaging device, such that two scan cones ate generated.
55. The imaging device of claim 51, wherein at least two
transducers are mounted at different locations along the central
axis of the imaging device.
56. The imaging device of claim 51, wherein at least two
transducers are mounted adjacent to one another in a plane
extending substantially perpendicular to the central longitudinal
axis of the scanning assembly, thereby increasing an angular range
of the scanning assembly and reducing an operating range of the
scanning assembly.
57. The imaging device of claim 51, wherein at least two
transducers are configured to be operated at different scanning
frequencies to image different tissue types or structures.
58. A method of placing a tip of a diagnostic or therapeutic
assembly at a specific location in tissue, comprising: forming an
image using an external imaging system; advancing an imaging device
toward a general area of tissue with guidance from the image
produced by the external imaging system; advancing the imaging
device to a precise location guided by an image produced using
signals from the imaging device; and performing a diagnostic or
therapeutic procedure at the location.
59. The method of claim 58, further comprising: advancing a
pre-loaded diagnostic or therapeutic assembly co-axially over the
imaging device; and withdrawing co-axially the imaging device from
a lumen of the diagnostic or therapeutic assembly, wherein
performing a diagnostic or therapeutic procedure at the location
comprises performing a diagnostic or therapeutic procedure at the
location using the diagnostic or therapeutic assembly.
60. The method of claim 58, wherein the method is employed to
perform a diagnostic procedure.
61. The method of claim 60, wherein the diagnostic procedure is one
of a general biopsy procedure, a breast biopsy procedure, a
prostate biopsy procedure, an aspiration procedure, an
amniocentesis procedure, a cordocentesis procedures, or a
transabdominal chorionic villus sampling procedure.
62. The method of claim 58, wherein the method is employed to
perform a therapeutic procedure.
63. The method of claim 62, wherein the therapeutic procedure is
one of RF ablation, a chemical injection, or a brachytherapy seed
placement procedure.
64. The method of claim 58, wherein a lesion to be diagnosed or
treated is less than .about.3 millimeters in size.
65. A method of placing a tip of a diagnostic or therapeutic
assembly at a specific location in tissue, comprising: palpating a
suspect lesion; advancing an imaging device toward a general area
of tissue based on a general location of the palpated lesion;
advancing the imaging device to a precise location of the palpated
lesion guided by images produced using signals from the imaging
device; and performing a diagnostic or therapeutic procedure at the
location.
66. The method of claim 65, further comprising: advancing a
pre-loaded diagnostic or therapeutic assembly co-axially over the
imaging device; withdrawing co-axially the imaging device from a
lumen of the diagnostic or therapeutic assembly, wherein performing
a diagnostic or therapeutic procedure at the location comprises
performing a diagnostic or therapeutic procedure at the location
using the diagnostic or therapeutic assembly.
67. The method of claim 65, wherein the method is employed to
perform a diagnostic procedure.
68. The method of claim 67, wherein the diagnostic procedure is one
of a general biopsy procedure, a breast biopsy procedure, a
prostate biopsy procedure, an aspiration procedure, an
amniocentesis procedure, a cordocentesis procedure, or a
transabdominal chorionic villus sampling procedure.
69. The method of claim 65, wherein the method is employed to
perform a therapeutic procedure.
70. The method of claim 69, wherein the therapeutic procedure is
one of a RF ablation, a chemical injection, or a brachytherapy seed
placement procedure.
71. The method of clam 65, where the lesion to be diagnosed or
treated is less than .about.3 millimeters in size.
72. A method of imaging using an imaging device, the method
comprising: providing a rigid imaging device configured to rotate
or oscillate a transducer in a housing of the imaging device, while
recording changes in an angle of the housing with respect to a
patient, to sweep out a forward-looking conical image; and rotating
or oscillating the transducer in the housing to produce a
forward-looking conical image.
73. The method of claim 72, wherein the rigid imaging device is one
of a rigid imaging needle device, a rigid imaging drill device, or
a rigid imaging reamer device.
74. A method of imaging using an imaging device having a scanning
assembly, the method comprising: a) providing a sector scanning
mechanism configured to oscillate a transducer in the scanning
assembly to sweep out a sector image; and b) oscillating the
transducer in the scanning assembly to produce a sector image.
75. The method of claim 74, further comprising: c) rotating or
oscillating the transducer in the scanning assembly in a plane
perpendicular to a central axis of the imaging device, while
recording changes in an angle of a housing of the imaging device
with respect to a patient; d) collecting all returned image data;
and e) constructing a three-dimensional forward-looking conical
image.
76. The method of claim 75, wherein maximum and minimum angles of
the scanning assembly with respect to the central axis of the
imaging device are adjustable within a range of .about.0.degree. to
.about.180.degree..
77. The method of claim 75, wherein maximum and minimum angles of
the scanning assembly with respect to the central axis of the
imaging device ate adjustable within a range of .about.60.degree.
to .about.120.degree..
78. The method of claim 75, wherein step b) is performed
continuously during step c).
79. The method of claim 75, wherein steps b)-c) produce a spiral
scan.
Description
[0001] This application claims priority to U.S. Provisional
Application No. 60/837,320 filed Aug. 14, 2006, which is herby
incorporated in reference in its entirety.
BACKGROUND
[0002] 1. Field
[0003] An Imaging device, Imaging System, and Methods of Imaging
are disclosed herein.
[0004] 2. Background
[0005] Imaging devices, imaging systems, and methods of imaging are
known. However, such known imaging assemblies, imaging systems, and
methods of imaging suffer from various disadvantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Embodiments will be described in detail with reference to
the following drawings in which like reference numerals refer to
like elements, and wherein:
[0007] FIG. 1 is a schematic block diagram of an imaging system
according to an embodiment;
[0008] FIG. 2A is a cross-sectional side view of an imaging device
according to an embodiment;
[0009] FIG. 2B is a cross-sectional side view of the transducer of
FIG. 2A;
[0010] FIG. 2C is a cross-sectional side view of the imaging device
of FIG. 2A disposed within a diagnostic or therapeutic
assembly;
[0011] FIG. 2D is a flow chart of a method of placing a tip of a
diagnostic or therapeutic assembly according to an embodiment;
[0012] FIG. 2E is a flow chart of a method of placing a tip of a
diagnostic or therapeutic assembly according to another
embodiment;
[0013] FIG. 2F is a cross-sectional side view of an alternative
embodiment of an imaging device;
[0014] FIG. 2G is a perspective view of the imaging drill bit of
FIG. 2F;
[0015] FIG. 3A is a cross-sectional side view of an imaging device
according to another embodiment;
[0016] FIG. 3B is a cross-sectional side view of the imaging device
of FIG. 3A disposed within a biopsy or therapeutic assembly;
[0017] FIG. 4 is a cross-sectional side view of an imaging device
according to another embodiment;
[0018] FIG. 5 shows a cartooned example of an image that may be
produced by an imaging device according to embodiments disclosed
herein, including a forward-looking conical section of tissue
displayed in a circular format;
[0019] FIG. 6A is a cross-sectional side view of an imaging device
according to another embodiment;
[0020] FIG. 6B is an enlarged view of the scanning assembly of FIG.
6A;
[0021] FIG. 7A is a cross-sectional side view of an imaging device
according to another embodiment;
[0022] FIG. 7B is an enlarged view of the scanning assembly of FIG.
7A;
[0023] FIG. 8A is a cross-sectional side view of an imaging device
according to another embodiment;
[0024] FIG. 8B is an enlarged view of the scanning assembly of FIG.
8A;
[0025] FIG. 9A is a cross-sectional side view of an imaging device
according to another embodiment;
[0026] FIG. 9B is a perspective view of the sector scanning
mechanism of FIG. 9A;
[0027] FIG. 9C is a cross-sectional side view of an imaging device
according to another embodiment;
[0028] FIG. 9D is a perspective view of the sector scanning
mechanism of FIG. 9A;
[0029] FIG. 10A is a cross-sectional perspective side view of an
imaging device according to another embodiment;
[0030] FIG. 10B is a perspective view of the sector scanning
mechanism of FIG. 10A;
[0031] FIG. 10C is a cross-sectional perspective view of an imaging
device according to another embodiment;
[0032] FIGS. 11A-11C are perspective views of scanning assemblies
according to embodiments;
[0033] FIG. 12 is a cross-sectional side view of an imaging device
according to another embodiment; and
[0034] FIGS. 13A-13C are flowcharts of methods of imaging according
to embodiments.
DETAILED DESCRIPTION
[0035] Many medical diagnoses and therapies are performed with the
aid of a needle. In some cases cells or fluids are removed from the
suspect tissue for examination ex-vivo to determine the state of
the tissue or contents of the cells or fluids. Once the diagnosis
has been made, needles may be use to deliver therapies in a
minimally invasive fashion. These therapies may involve, for
example, Radio Frequency (RF) ablation, chemical ablation, laser
ablation, vessel cautery, radioactive seed implants, cryotherapy,
and photodynamic therapy. Frequently the accuracy with which a
needle may be placed in the tissue to be examined or treated is
insufficient, thereby requiring more invasive surgical approaches.
To assist in the placement of these needles, image-guided methods
have been developed using various medical imaging modalities. These
imaging modalities are typically standard imaging systems that have
been adapted to show the path of the needle as it is advanced to
the tissue of interest. In some cases, however, a more precise
method of guiding a needle is beneficial. This is particularly true
when the size of the tissue to be examined or treated is small
compared to the resolution of the standard imaging system. It may
also be true when the position of the tissue is significantly
displaced by the advance of the needle toward it. Lesions smaller
than, for example, .about.3 mm in size may be difficult to
visualize with external image guidance systems.
[0036] Breast cancer is a major health problem for women. Early
detection and treatment of tumors is crucial to the long-term
survival of patients. As such, women are encouraged to perform
regular self-examinations and receive an annual breast scan after
the age of forty. When suspicious lesions are found, they are
typically subjected to needle biopsy to determine the nature of the
cells that form the lesion. This is done by inserting a large
diameter needle, typically under image guidance, into the suspect
tissue whereby a small sample is suctioned into the tip of the
needle, removed from the body, and examined under microscope by a
cytopathologist. This biopsy is often performed with external
ultrasonic or mammographic image guidance of the trajectory of the
needle from the skin surface of the breast to the lesion. It is
important to verify the position of the needle tip relative to the
suspect lesion before acquiring the tissue sample for further
evaluation. A failure to do so may result in adjacent normal tissue
being mistaken for the suspect tissue. On occasion the advance of
the biopsy needle may displace the suspect tissue from its original
position thereby making the collection of the desired tissue
difficult or impossible.
[0037] Another problem with this approach is that not all lesions
visible on x-ray mammography can also be seen using external
ultrasound. In addition, it is also very difficult to obtain image
guidance using either external ultrasound or mammography for
lesions that are in, for example, the axilla or very posterior
lesions near the patient's chest wall.
[0038] Image guidance also helps physicians to position needles,
and similar devices such as reamers and drills, for other medical
procedures, such as drainage, precision injections, pedicle screw
placements, amniocentesis, cordocentesis, brachytherapy seed
implantations, and transabdominal chorionic villus sampling. In all
of these cases, it may be difficult to maintain the trajectory of
the needle within the image plane or field of view of the external
imaging system. In cases where very precise needle positioning is
required in soft tissues, the resolution of the external imaging
system may be inadequate to ensure that the needle, reamer or drill
tip is in the desired location.
[0039] Embodiments relate generally to the fields of diagnostic and
therapeutic medicine, and more specifically, to an imaging device
which may include may be deployed within a needle or other
diagnosis therapy device to aid in guiding the needle or other
diagnosis therapy device to a precise location for diagnoses and
treatment of, for example, soft tissue lesions, and methods of
imaging using such an imaging device. At least one embodiment
described herein incorporates a very low cost imaging system and an
inexpensive imaging device design that may be sold as a disposable
device. While an external imaging system, or previously acquired
external images, may be used to position a tip of the imaging
device in the vicinity of suspect tissue, an operator of the
imaging device according to embodiments may switch to an integrated
imaging device and tip imaging system, and more precisely direct
the tip of the imaging device to the desired location when a lesion
is very small. The combined imaging system also takes up little
space and may be integrated into the bed or procedure table that a
physician would normally use.
[0040] All of the embodiments disclosed herein allow for a more
accurate placement of a tip of a needle, reamer or drill assembly
by virtue of imaging tissue structures that lie distal to the tip
and advancing accordingly to a desired location. The imaging
device, imaging system, and methods of imaging according to
embodiments allow diagnostic or therapeutic needle-based (reamer or
drill based) procedures, for a more accurate sampling of the
suspect tissue for later examination and in some cases, the direct
treatment of a lesion using various therapies or placement of
pedicle screws or other like devices.
[0041] Embodiments disclosed herein allow for the visualization of
smaller lesions during diagnostic and therapeutic procedures, a
more accurate sampling of suspect tissue for later examination and
in some cases, direct treatment of a lesion using various
therapies. The imaging device, imaging system, and methods of
imaging may include an imaging device that may fit inside, for
example, a diagnostic, biopsy, drainage, or therapeutic assembly.
The imaging device may reside inside the diagnostic, biopsy,
drainage, or therapeutic assembly as the combined device is
advanced to a desired location. Images may be produced that allow
for accurate placement of the diagnostic, biopsy, drainage,
therapeutic assembly or pedicle drill. A transducer may be located
near a distal tip of the imaging device at an angle relative to a
central longitudinal axis (referred to hereinafter as the "the
central axis") of the imaging device. The transducer may be housed
in a scanning assembly that sweeps the transducer through an angle
of acoustic scan. When the imaging device is rotated, the scanning
assembly may transmit and collect echoes from a forward-looking
sector or conical section of tissue that lies just distal to a
distal most tip of the imaging device. An image may be formed when
the imaging device is rotated. As a sector angle may be swept out,
the image in the corresponding sector of the display may be
updated. The imaging device may be rotated through, for example, a
full .about.360 degree sweep to display the entire conical section
of tissue. Alternatively, the imaging device may be swept
repeatedly back and forth over a narrower sector to transmit and
receive the scan lines and update a display of an imaging system
repeatedly only over the narrow sector. Using the images generated
by the imaging device, the operator may manually maneuver the tip
of the imaging device to a precise location that appears in the
display. A second assembly for diagnosis or therapy may be
preloaded onto the imaging device and when the imaging device is in
place the second assembly may be advanced over the imaging device
in a co-axial fashion to the desired location. Once the diagnostic
or therapy assembly is in place, the imaging device may be
withdrawn and the standard procedure may continue.
[0042] In another embodiment, both a forward-looking conical
section of tissue and a forward-looking angular sector of tissue
may be interrogated. In this case, the sector image may be made by
"wobbling" the scanning assembly back-and-forth through a desired
sector angle. This wobbling action varies the angle of the
transducer with respect to a central axis of the imaging device.
The wobbling may be accomplished through a variety of mechanical
mechanisms that allow a force to be exerted on the scanning
assembly while a second angle encoder is recording a position of
the proximal portion of the mechanism.
[0043] If the operator desires to change the forward-looking cone
angle, he or she may do so by adjusting and setting the transducer
angle with respect to the central axis of the imaging device.
Further, if the operator wishes to interrogate, for example, an
entire three-dimensional forward-looking conical volume this may
also be done by sweeping out a series of sectors as the imaging
device is rotated in the tissue about the central axis of the
imaging device. Analogously, this may be achieved by rotating the
scanning assembly though a series of cones while varying the angle
from a maximum possible angle with respect to the central axis of
the imaging device to in-line with the central axis of the imaging
device. Software may be provided to keep track of both the
rotational angle of the housing and the angle of the transducer
about the central longitudinal axis of the scanning assembly, and
appropriately recording these along with the echo data that returns
to the transducer in each position.
[0044] As set forth above, the imaging device according to certain
embodiments disclosed herein may be used with or incorporated into
a diagnostic or therapeutic assembly. For example, a standard
diagnostic or therapeutic assembly may be advanced or retracted
over the imaging device co-axially. Such a combination allows the
diagnostic or therapeutic assembly to be accurately directed to an
area of interest based on information in the images produced using
signals from the imaging device. For example, the imaging device
may fit inside a diagnostic or therapeutic assembly, such as a
biopsy, drainage, or other type therapy assembly. The imaging
device may reside inside the diagnostic or therapy assembly as the
combined device is advanced to a desired location. Two-dimensional
or three-dimensional images using signals from the imaging device
may be produced that allow for the accurate placement of the
diagnostic or therapy assembly.
[0045] In an alternative embodiment, the imaging device may take
the form of an imaging drill or imaging reamer that may be used,
for example, to create precisely located pilot holes in the
pedicles of the vertebrae for spinal fixation procedures. In such
an embodiment, a fluted drill-like surface or a ribbed reamer
surface may be substituted for the smooth surface of the imaging
device.
[0046] Further, the imaging device according to certain embodiments
disclosed herein may be manually rotated or electronically rotated.
Also, the imaging device according to certain embodiments disclosed
herein may be rotated .about.360.degree. to produce an image, for
example, a forward-looking circular or conical image. The
forward-looking circular or conical image may be representative of
tissue on a surface of a cone. Alternatively, the scanning assembly
according to certain embodiments disclosed herein may be rotated
about the central longitudinal axis of the scanning assembly to
scan a sector image, for example, a forward-looking sector image.
Additionally, the scanning assembly according to certain
embodiments may be rotated to produce a three-dimensional
volumetric image by rotating a scanned sector image.
[0047] In the following discussion, the imaging device according to
embodiments is disclosed as utilized with an imaging system shown
in FIG. 1 and described in U.S. patent application Ser. No.
11/053,141, which is hereby incorporated by reference. However, it
should be understood that the imaging device according to
embodiments may be utilized with other systems as well.
[0048] As set forth above, an imaging system and an imaging device
according to embodiments are disclosed herein. As discussed above,
FIG. 1 shows an imaging system described in U.S. patent application
Ser. No. 11/053,141, which is hereby incorporated by reference.
This system is a low-cost ultrasonic imaging system. Unlike
conventional mechanically steered imaging systems, this system does
not require a motor to rotate or wobble the scanning assembly.
Instead, driving the scanning assembly may be done manually by the
operator and the image displayed as the transducer is swept through
a section of tissue to be imaged. In this system, the imaging
device 10 may emit a transmit signal and receive echoes, which may
be carried to an electronics module 18 by a cable 12. An angle of
rotation of the imaging device 10 may be encoded by an angle
encoder 16 and the quadrature signals may be carried from, and
power may be carried to the angle encoder 16 via a small
multi-conductor cable 24.
[0049] Inside the electronics module 18 the echoes may be
demodulated and passed to a Central Processor 20 for display on a
monitor 21. In the Central Processor 20, the demodulated echo data
may be combined with the image assembly angle information to place
the echo line, representing the tissue being imaged, in the correct
geometric location as described in co-pending U.S. patent
application Ser. No. 11/437,687, filed May 22, 2006, entitled
"Apparatus and Method for Rendering for Display Forward-Looking
Image Data" (Attorney Docket No. NOVS-0004), which is hereby
incorporate by reference. Finally, the image may be rendered for
display on the monitor 21.
[0050] FIG. 2A is a side view of an imaging device according to an
embodiment. FIG. 2B is a cross-sectional side view of the
transducer of FIG. 2A. FIG. 2C is a cross-sectional side view of
the imaging device of FIG. 2A disposed within a diagnostic or
therapeutic assembly.
[0051] The imaging device 200 of FIG. 2A maybe in the form of an
imaging needle assembly, and may be designed to form a conical
forward-looking image 245, as shown in FIG. 2A. The imaging device
200 may include a housing 230. An angle encoder 240 may be provided
to encode a rotational angle of the housing 230 relative to the
rest of the device and a hand grip. The grip, which may be in the
form of knurled sleeves 238, 242, may be provided to assist an
operator in grasping the housing 230. A transducer 234 may be
positioned on a distal tip 236 of the imaging device 200. The
transducer 234 may include, for example, an ultrasonic transducer,
such as the transducer shown in FIG. 2B. The transducer 234 may be
oriented along a line C2 at an angle .PHI.1 from a central axis C1
of the imaging device 200 between .about.0 degrees and .about.90
degrees. For the purpose of illustration, an angle in the range of
.about.10 degrees and .about.30 degrees is shown. The transducer
234 may communicate through a coaxial cable 232 and a connector 246
to an imaging system, such as the imaging system as shown in FIG.
1.
[0052] As shown in FIG. 2B, the transducer may include, for
example, a face plate 250 that serves as a matching layer 252, a
piezoelectric transducer 254, and an absorptive backing layer 256
that attenuates the sound waves emanating for a rear side of the
piezoelectric transducer 254. The matching layer 252 may be made of
an appropriate material such that it is, for example, an
approximately 1/4 wavelength thick and has an acoustic impedance
that is the geometric mean of the piezoelectric material and the
body tissue. It may also be made of multiple layers of
appropriately selected materials so as to broaden a bandwidth of
the transmitted and received sound waves. A frequency of the
transducer may be selected to provide sufficient resolution to make
adequate images of small structures, for example, <.about.3 mm
an operator wishes to locate and yet allow for sufficient
penetration so the operator may visualize a larger landscape that
aids in locating more distant lesions. An aperture (or size and
shape) of the transducer may be configured to fit within the
imaging device 200 and may be used primarily as an unfocused
near-field imaging device, although it may include a lens for
focusing, if desired.
[0053] The angle encoder 240 may be formed integral with the
imaging device 200. The angle encoder 240 may include a cable 243
and a connector 244.
[0054] In operation, an operator may rotate the housing 230, for
example, by grasping the knurled sleeves 238 or 242 between the
thumb and index finger. The integral angle encoder 240 may encode
the rotational angle in real time as the housing 230 is rotated.
Echo information may be carried back to an electronics module 18 of
an imaging system, such as the imaging system shown in FIG. 1, by
the coaxial cable 232 and the connector 246. Angle information may
be carried back to the electronics module 18 via the cable 243
through the connector 244. As the operator sweeps out an angular
sector by rotating the housing 230, the image may be updated in
real time on the display module 21.
[0055] FIG. 2C is a cross-sectional side view of the imaging device
of FIG. 2A disposed within a diagnostic or therapeutic assembly.
The imaging device may be in the form of an imaging needle assembly
and the diagnostic or therapeutic assembly in the form of a
diagnostic or therapeutic needle assembly. The distal portion 235
of the imaging device 200 from the knurled sleeve 238 on may fit
inside of an exterior housing 217 of the diagnostic or therapeutic
assembly 215, as shown in FIG. 2C. When a desired location of the
distal tip 236 of the imaging device 200 has been reached, the
imaging device 200 may be removed from a lumen 219 of the
diagnostic or therapeutic assembly 215 and the standard procedure
may continue. The diagnostic or therapeutic assembly 215 may
further include a connector 218, such as a leur connector.
[0056] FIG. 2D is a flow chart of a method of placing a tip of a
diagnostic or therapeutic assembly at a specific location in tissue
according to an embodiment. The imaging device may be in the form
of an imaging needle assembly and the diagnostic or therapeutic
assembly in the form of a diagnostic or therapeutic needle
assembly. The method may include forming an image using an external
imaging system, such as a commercially available ultrasonic imaging
system (step 2D10). An imaging device may then be advanced toward a
general area of tissue with guidance from images produced by the
external imaging system (step 2D20). Next, the imaging device may
be advanced to a precise location guided by images produced using
signals from the imaging device (step 2D30). Thereafter, a
pre-loaded diagnostic or therapeutic assembly may be advanced
co-axially over the imaging device (step 2D40), and the imaging
device co-axially withdrawn from a lumen of the diagnostic or
therapeutic assembly (step 2D50). A diagnostic or therapeutic
procedure may then be performed at the location using the
diagnostic or therapeutic assembly (step 2D60). This method may be
employed in, for example, general biopsy procedures, breast biopsy
procedures, prostate biopsy procedures, aspiration procedures,
amniocentesis procedures, cordocentesis procedures, and
transabdominal chorionic villus sampling procedures. Further, the
method may be employed to perform a therapeutic procedure, such as
RF ablation, a chemical injection, and a brachytherapy seed
placement procedure. With this method, a lesion to be diagnosed or
treated may be less than .about.3 millimeters in size.
[0057] FIG. 2E is a flow chart of a method of placing a tip of a
diagnostic or therapeutic assembly at a specific location in tissue
according to an embodiment. The imaging device may be in the form
of an imaging needle assembly and the diagnostic or therapeutic
assembly in the form of a diagnostic or therapeutic needle
assembly. The method may include palpating a suspect lesion (step
2E10). An imaging device may then be advanced toward a general area
of tissue with guidance from images produced by the external
imaging system (step 2E20). Next, the imaging device may be
advanced to a precise location guided by images produced using
signals from the imaging device (step 2E30). Thereafter, a
pre-loaded diagnostic or therapeutic assembly may be advanced
co-axially over the imaging device (step 2E40), and the imaging
device may be co-axially withdrawn from a lumen of the diagnostic
or therapeutic assembly (step 2E50). Then, a diagnostic or
therapeutic procedure may be performed at the location using the
diagnostic or therapeutic assembly (step 2E60). This method may be
employed in, for example, general biopsy procedures, breast biopsy
procedures, prostate biopsy procedures, aspiration procedures,
amniocentesis procedures, cordocentesis procedures, and
transabdominal chorionic villus sampling procedures. Further, the
method may be employed to perform a therapeutic procedure, such as
RF ablation, a chemical injection, and a brachytherapy seed
placement procedure. With this method, a lesion to be diagnosed or
treated may be less than .about.3 millimeters in size.
[0058] As set forth above, in alternative embodiments, the imaging
device may take the form of an imaging drill or imaging reamer that
may be used, for example, to create precisely located pilot holes
in the pedicles of the vertebrae for spinal fixation procedures. In
such embodiments, a fluted drill-like surface or a ribbed reamer
surface may be substituted for the smooth surface of the imaging
device. Examples of such alternative embodiments are shown in FIGS.
2F and 2G. That is, FIG. 2F shows an imaging drill bit 233 provided
as a distal end 236' of the imaging device 200'. The imaging drill
bit 233 and housing 230' may be rotated by rotating knob or sleeve
298'. An angle encoder 240', including photo interrupter 245' and
slit wheel 244', may be provided housed within outer sleeve 230a'.
A grip, which may be in the form of knurled knob 238', may be
provided on the outer sleeve 230a', to allow either rotating or
oscillating motion. Rotation creates the circular image 245'
depicted.
[0059] FIG. 2G shows the imaging drill bit 233' depicted with the
transducer 234' and cutting edges 233a' along both sides of four
flutes along a tapered body connected to straight shank 233b'. The
straight shank 233b' may mount permanently in the imaging device
200'.
[0060] FIG. 3A shows another embodiment of an imaging device. FIG.
3B is a cross-sectional side view of the imaging device of FIG. 3A
disposed within a biopsy or therapeutic assembly. The imaging
device may be in the form of an imaging needle assembly and the
diagnostic or therapeutic assembly in the form of a diagnostic or
therapeutic needle assembly. In FIGS. 3A-3B, like reference
numerals have been used to indicate like elements to the embodiment
of FIGS. 2A-2B, and repetitive disclosure has been omitted.
[0061] The imaging device 300 of FIGS. 3A-3B may be in the form of
an imaging needle assembly. In the embodiment of FIGS. 3A-3B, a
distal end 236 of the imaging device 300 may be substantially blunt
rather than sharp. Further, the imaging device 300 may fit
completely inside a biopsy or therapeutic assembly 315, as shown in
FIG. 3B, and provide images of tissue at a distal-most tip of the
biopsy or therapeutic assembly 315. An imaging device 300 such as
that shown in FIG. 3A is particularly useful in aiding precise
placement of a second tip 316, as shown in FIG. 3B, that may be
used for, for example, a drainage procedure, chemical injection,
amniocentesis, cordocentesis, or transabdominal chorionic villus
sampling. As the biopsy or therapeutic assembly 315 is advanced
toward a target tissue, images may be obtained and mid-course
corrections may be made to ensure that the tip of the biopsy or
therapeutic assembly 315 may be precisely located in, for example,
the desired tissue, vessel, lumen, or any other anatomical
structure. The biopsy or therapeutic assembly 315 may further
include a connector 318, such as a leur connector.
[0062] FIG. 4 shows another embodiment of an imaging device. In
FIG. 4, like reference numerals have been used to indicate like
elements to the embodiments of FIGS. 2A-3B, and repetitive
disclosure has been omitted.
[0063] The imaging device 400 of FIG. 4 may be in the form of an
imaging needle assembly. In the embodiment of FIG. 4, a treatment
device, shown in this embodiment as an ablation device 449, such as
a radiofrequency (RF) ablation antenna, may be incorporated into
the distal end 436 of the imaging device 400 so that tissue in a
target location may be ablated or cauterized. A central axis of the
imaging device 400 is designated by reference numeral D1 in FIG. 4.
The ablation device 449 may be located along a line D3, as shown in
FIG. 4, at an angle .PHI.2, shown in this embodiment .about.180
degrees of rotation around the central axis of the imaging device
from a line D2 on which the transducer 434 is positioned. The
location of the ablation device 449 may be displayed on images that
are created to allow the operator to image, then ablate or
cauterize specific areas of tissue that appear in the image, such
as a conical forward-looking image. Ablation energy may be carried
to the ablation device 449 via cable 450 and attached to the
electronics module 18 via a connector 446. The specific shape of
the ablation device 449 may be designed to ablate or cauterize a
variety of small volume shapes near the tip or distal end 436 of
the imaging device 400. Likewise, the specific electrical signal
sent to the ablation device 449 may be optimized for either
ablation or cauterization.
[0064] FIG. 5 shows an example of how an imaging device according
to embodiments may be displayed on a forward-looking guidance
image. The image may be displayed as a two-dimensional image or as
described in co-pending U.S. patent application Ser. No.
11/437,687, filed May 22, 2006, entitled "Apparatus and Method for
Rendering for Display Forward-Looking Image Data" (Attorney Docket
No. NOVS-0004), which is hereby incorporated by reference. As the
imaging device is rotated, line 552, for example, of the image 551
displays a direction from which scan lines are being received. This
corresponds to an angular orientation of the transducer. The
location 554 where the therapy will occur may also be displayed and
may be rotated with the transducer albeit, for example, .about.180
degrees away from where the new image lines are received. The
center axis 553 of the imaging device may be stationary. Tissue
structures 555, 556, 557, 558 will be seen if they intersect the
forward-looking conical surface that is being swept out by the
transducer.
[0065] As set forth above, the imaging device according to the
embodiments of FIGS. 2A-4 are shown as forming a conical
forward-looking image. However, a need may exist to scan in a
sector mode, in addition to a circular or conical mode. The
following embodiments accomplish this via a sector scanning
mechanism that wobbles or oscillates a scanning assembly in order
to scan a sector image.
[0066] FIG. 6A shows another embodiment of an imaging device. FIG.
6B is an enlarged view of the scanning assembly of FIG. 6A. In
FIGS. 6A-6B, like reference numerals have been used to indicate
like elements to the embodiments of FIGS. 2A-4, and repetitive
disclosure has been omitted.
[0067] The imaging device 600 of FIGS. 6A-6B may be in the form of
an imaging needle assembly. The embodiment of FIGS. 6A-6B includes
a sector scanning mechanism 690 by which an angle .PHI.3 of a
transducer 634a of the scanning assembly 666 from a central axis E1
of the imaging device 600 may be varied, thereby forming a sector
image 645 from a distal end 636 of the imaging device 600. The
embodiment shown in FIG. 6A utilizes a drive shaft 673 that runs a
length of the imaging device 600 and terminates at one end 636 with
a gear 672b that drives the scanning assembly 666 (mounted on axle
666b) through a sector angle and at the other end 639 in a knob 698
after passing through a slotted encoder wheel 684 that allows the
sector angle to be recorded.
[0068] This type of scanning is frequently referred to as
mechanical "wobble" scanning. The sector image 645 that is produced
may be manually swept out around central axis E1 by the operator
when he or she rotates knurled sleeve 638 at the end 637 of the
housing 630. The mechanism shown, in this embodiment, may
incorporate a bevel gear 672a and bevel gear 672b that wobble the
scanning assembly 666 on the axle 666b in response to the drive
shaft 673 being oscillated back-and-forth by the turning of the
knurled sleeve 638. The drive shaft 673 may be held in place by a
support fixture 678 that captures a bearing 679, inside of which
the drive shaft 673 rotates.
[0069] The drive shaft 673 may also be connected to an angle
encoder 680. The angle encoder 680 may include a slit wheel 684
around which a photo interrupter 685 is positioned. The photo
interrupter 685 may include a light emitting diode 687 and a photo
detector 686 that sense each time a slit on the angle encoder slit
wheel 684 passes between them. This may be similar to the angle
encoding function performed by an angle encoder 640 for the imaging
device 600 itself The angle encoder 640 of the imaging device 600
may include a slit wheel 649 and a photo interrupter 646, which may
include a light emitting diode 647 and a photo detector 648.
However, the photo interrupter 685 may be attached to and rotate
with the housing 630. The wiring of the two photo interrupters is
not shown for clarity; however, it would be obvious to one skilled
in the art.
[0070] FIG. 7A shows another embodiment of an imaging device. FIG.
7B is an enlarged view of the scanning assembly of FIG. 7A. In
FIGS. 7A-7B, like reference numerals have been used to indicate
like elements to the embodiments of FIGS. 2A-4 and 6A-6B, and
repetitive disclosure has been omitted.
[0071] The imaging device 700 of FIGS. 7A-7B may be in the form of
an imaging needle assembly. The embodiment of FIGS. 7A-7B may
incorporate a sector scanning mechanism 790 to vary the angle of or
wobble the scanning assembly 766. In FIG. 7A, F1 represents a
central longitudinal axis of the imaging device 700. The sector
scanning mechanism may be in the form of a draw-string mechanism
that allows the scanning assembly 766 mounted on axle 766b to be
rotated an angle .PHI.4 with respect to the central axis of the
imaging device 700. The draw-string mechanism 794 may include pull
wires 791 that run a predetermined length along the imaging device
700 and wrap around a pulley 792 that communicates with an angle
encoder 780. The angle encoder 780 may include a slotted encoder
wheel 784 driven by the pulley 792 that allows an angle of the axle
793 to be recorded via photo interrupter 785. A knob 796 may be
provided on one end of the axle 793 to rotate the axle 793.
[0072] In this embodiment, the pull wires or draw strings 791 may
be used to drive the scanning assembly 766 back-and-forth through a
desired sector angle to produce a sector image 745. The draw
strings or pull wires 791 may wrap one or mote times around the
pulley 792, which in turn may be connected to the axle 793 that is
rotated when the knob 796 is rotated. The encoder slit wheel 784
may be positioned on the other end of the axle 793 to trigger the
photo interrupter 785, and thereby encode the angle of the pulley
792. The radius of the pulley 792 may be smaller or larger than the
radius of the scanning assembly 766 to affect a gearing up or a
gearing down.
[0073] The angle encoder 740 of the imaging device 700 may include
a slit wheel 749 and a photo interrupter 746, which may include a
light emitting diode 747 and a photo detector 748. However, the
photo interrupter 785 may be attached to and rotate with the
housing 730. The wiring of the two photo interrupters is not shown
for clarity; however, it would be obvious to one skilled in the
art.
[0074] FIG. 8A shows another embodiment of an imaging device. FIG.
8B is an enlarged view of the scanning assembly of FIG. 8A. In
FIGS. 8A-8B, like reference numerals have been used to indicate
like elements to the embodiment of FIGS. 2A-4 and 6A-7B, and
repetitive disclosure has been omitted. The imaging device 800 of
FIGS. 8A-8B may be in the form of an imaging needle assembly. The
embodiment of FIGS. 8A-8B may include a sector scanning mechanism
890 to vary the angle of or wobble the scanning assembly 866 to
form a sector image 845. In FIGS. 8A-8B, G1 represents a central
axis of the imaging device 800. The sector scanning mechanism 890
allows the scanning assembly 866 mounted on axle 866b to be rotated
an angle .PHI.5 with respect to the central axis of the imaging
device 800. This mechanism employs a concentric "drivetube"
hypotube or inner tube 890a that has an angled slot 892 at a distal
end that engages a pin 894 on the scanning assembly 866. An angle
encoder 880, which may include a slotted encoder wheel 884, allows
an angle of the inner tube 890a to be recorded. In this embodiment,
the concentric "dtivetube" hypotube drive or inner tube 890a on the
inside of the housing 830 may be used as a drive shaft. At the
distal end of the inner tube 890a, the angled slot 892 may be
provided engaged by the pin 894 on the scanning assembly 866. When
the tube 890a is rotated, the angled slot 892 pushes the pin 894
proximal and distal, thereby rotating the scanning assembly 866
back and forth over the sector angle to produce the sector image
845. The inner tube 890a may have a second oppositely angled slot
on the other side (not shown) so as to engage a second pin (not
shown) on the far side of the scanning assembly 866. The axle 866b
(which corresponds to the central longitudinal axis of the scanning
assembly) may, in fact, need to have an "omega" shape so as not to
interfere with the inner tube 890a or the inner tube 890a may need
to have part of its wall removed where the axle 866b enters the
housing 830. This is not shown for simplicity. At the proximal end
837 of the housing 830, the inner tube 890a may have an encoder
slit wheel 884 attached thereto which rotates with the inner tube
890a. As the encoder slit wheel 884 rotates, the photo interrupter
885 may generate pulses in response to each slit as it interrupts
the light path from the light emitting diode 887 to the photo
detector 886.
[0075] The angle encoder 840 of the imaging device 800 may include
a slit wheel 849 and a photo interrupter 846, which may include a
light emitting diode 847 and a photo detector 848. However, the
photo interrupter 885 may be attached to and rotate with the
housing 830. The wiring of the two photo interrupters is not shown
for clarity; however, it would be obvious to one skilled in the
art.
[0076] FIGS. 9A-10B show embodiments in which the scanning assembly
may be oscillated by a sector scanning mechanism. The imaging
device 900, 900, 1000, 1000a of each of FIGS. 9A-9B, 9C-9D, and
10A-10C may be in the form of an imaging needle assembly. FIGS.
9A-9B show an exemplary embodiment in which the sector scanning
mechanism may include a pull and retract mechanism. FIGS. 9C-9D
show an exemplary embodiment in which the sector scanning mechanism
may include cranks and a connecting rod. FIGS. 10A-10B show an
exemplary embodiment in which the sector scanning mechanism may
include an oscillating drive shaft driven by an oscillating output
mechanism. FIG. 10C shows an exemplary embodiment in which the
sector scanning mechanism may include an oscillating drive
motor.
[0077] In the embodiment of FIGS. 9A and 9B, a sector scanning
mechanism 990 may be provided in the form of a pull-and-retract
mechanism. The pull-and-retract mechanism may include a cable 991
that pulls the scanning assembly 966, mounted on a pivot 966b
through an angle via a pulley 992. The angularly displaced scanning
assembly 966 may be returned to its original position by a spring
994, 994a pulling in the opposite direction. The spring 994, 994a
may be connected to a base 995, 995a and to the scanning assembly
966 and/or the pulley 992, as shown in FIGS. 9A-9B.
[0078] In the embodiment of FIGS. 9C and 9D, a sector scanning
mechanism 990' may be provided in the form of a crank and rod
mechanism that pulls and pushes the scanning assembly 966'. The
crank and rod mechanism may include rod 991' connected to rotating
crank 992' and to the scanning assembly 966', which may be mounted
on pivot 966b'. The rotating crank 992' may be mounted on shaft
993' and may be driven by gear 996'. A spring 994a' may be attached
to base 995a' and scanning assembly 966' to prevent backlash.
[0079] The angle encoder 940 of the imaging device 900 may include
a slit wheel 949 and a photo interrupter 946, which may include a
light emitting diode 947 and a photo detector 948. However, the
photo interrupter 985 may be attached to and rotate with the
housing 930. The wiring of the two photo interrupters is not shown
for clarity; however, it would be obvious to one skilled in the
art.
[0080] In the embodiment of FIGS. 10A and 10B, a sector scanning
mechanism 1090 may be provided in the form of an oscillating drive
shaft 1095 driven by an oscillating output mechanism. That is,
rotary motion from a motor 1096 and encoder 1040 may be converted
to oscillating rotary motion by a small crank 1092 connected by a
connecting rod 1093 connected to a larger crank 1094. The
oscillating motion may be transmitted by an output or drive shaft
1095 to the scanning assembly 1066 where a pair of miter gears (not
shown) transmit the oscillation to a shaft perpendicular to that of
the drive shaft 1095. This right angle drive may be accomplished
with miter, bevel, hypoid, helical, or brequet gears. In this way,
the scanning assembly may be driven in a direction substantially
perpendicular to that of the output or drive shaft 1095.
[0081] That is, as shown in FIG. 10A, an imaging device 1000
according to this embodiment may include a scanning assembly 1066
disposed within housing 1030. The oscillating mechanism 1090 may be
provided to convert rotary motion into an oscillating motion.
[0082] As shown in FIGS. 10A and 10B, the sector scanning mechanism
1090 may include an input shaft 1091, an input crank 1092, a
connecting rod 1093, an output crank 1094, and an output shaft
1095. As the input shaft 1091 is rotated, the rotational motion may
be converted to an oscillating motion by the input crank 1092, the
connecting rod 1093, and the output crank 1094, so that the output
shaft 1095 may be oscillated about its central longitudinal axis.
The output shaft 1095 may be connected to the scanning assembly
1066 to rotate the transducer about an axis substantially
perpendicular to the central axis of the output shaft 1095.
[0083] The sector scanning mechanism 1090a of FIG. 10C may include
drive or output shaft 1095a. An oscillating motor 1096a and encoder
1040a may oscillate the drive or output shaft 1095a, thereby
oscillating the scanning assembly 1066a.
[0084] The imaging device of the embodiments of FIGS. 2A-4 and
6-10C are shown as forming a conical forward-looking image or a
forward-looking sector image. However, the imaging device of the
embodiments of FIGS. 2A-4 and 6-10C may be configured to produce
other shaped images if so desired. Further, the imaging device of
the embodiments of FIGS. 2A-4 and 6-10C may be mechanically or
electronically operated. Additionally, although the imaging device
of the embodiments of FIGS. 2A-4 and 6-10C are discussed as
utilizing an ultrasonic transducer, the imaging device of the
embodiments of FIGS. 2A-4 and 6-10C may utilize other types of
transducers, such as an optical transducer, if desired.
[0085] Additionally, the embodiments of FIGS. 6A-8B and 9A-10C each
include a sector scanning mechanism. One of ordinary skill in the
art would recognize that these embodiments may be combined to
produce desired scanning. Further, combining the sector scanning
mechanism and a rotating mechanism configured to rotate the imaging
device will allow the scanning, and thus imaging of volumes of
tissues.
[0086] Referring to FIGS. 6A-6B, 7A-7B, 8A-8B, 9A-9B, 9C-9D, and
10A-10C, the operator may rotate the imaging device 600, 700, 800,
900, 900', 1000, 1000a to form an image of the tissue on a surface
of a forward-looking conical surface or back and forth to form a
forward-looking sector image 645, 745, 845, 948, 1048 of the
tissue. If the operator desires, he/she can perform a series of
scanning assembly rotations and sector angle wobbles to manually
interrogate an entire three-dimensional volume of tissue in front
of the imaging device 600, 700, 800, 900, 900', 1000, 1000a. This
resultant three-dimensional echo data may then be displayed by
techniques common in the field to show all of the tissue in a
conical volume distal to the tip of the imaging device 600, 700,
800, 900, 900', 1000, 1000a.
[0087] That is, in addition to scanning a slice of anatomy, it may
be advantageous for certain applications, for example, certain
image reconstruction techniques, to scan volumes. Volumes may be
rapidly scanned by combining, for example, a rotary oscillation
with a sector scan to produce a volume scan. To accomplish this,
the mounting containing the sector scan mechanism may be made to
oscillate or rotate about a central axis of the imaging device. The
scanning assembly may be inclined at an angle where a midpoint of
the sector is at an angle to the central axis of the imaging device
that is half the total sector angle to most efficiently use the
available scanning time. This avoids "wasting time" repeatedly
scanning previously scanned tissue.
[0088] One exemplary embodiment of an imaging device configured for
volume scanning is shown in FIG. 12. The imaging device 1200 of
FIG. 13 may be in the form of an imaging needle assembly. Further,
the imaging device 1200 shown in FIG. 12 may include a scanning
assembly 1266 mounted within housing 1230. The sector scanning
mechanism 1290 may be driven by motor 1296. That is, output shaft
1291 may be attached to connector mechanism 1297 via drive shaft
1299a. Drive shafts 1299a and 1299b and connector mechanism 1297
also connect the motor 1296 to gear 1298a which mates with gear
1298b mounted on housing 1230 to rotate the imaging device 1200 in
a rotary motion.
[0089] FIGS. 13A-13C are flow charts of a method of imaging using
an imaging device according to embodiments. The method of FIG. 13A
includes providing a rigid imaging device configured to rotate or
oscillate a transducer in a housing of the imaging device, while
recording changes in an angle of the housing with respect to a
patient, to sweep out a forward-looking conical image (step 13A10).
The transducer is then rotated or oscillated in the housing to
produce a forward-looking conical image (step 13A20). The rigid
imaging device may be, for example, a rigid imaging needle device,
a rigid imaging drill device, or a rigid imaging reamer device.
[0090] The method of FIG. 13B includes providing a sector scanning
mechanism configured to oscillate a transducer in a scanning
assembly of an imaging device to sweep out a sector image (step
13B10). The transducer is then oscillated in the scanning assembly
to produce a two-dimensional forward-looking sector image (step
13B30).
[0091] The method of FIG. 13C includes providing a sector scanning
mechanism configured to oscillate a transducer in a scanning
assembly of an imaging device to sweep out a sector image (step
13C10). The transducer is oscillated in the scanning assembly to
produce a sector image (step 13C20). Then, the transducer is
rotated or oscillated in the scanning assembly in a plane
perpendicular to a central axis of the imaging device, while
changes in an angle of a housing of the imaging device with respect
to a patient are recorded (step 13C30). All of the returned data is
then collected (step 13C40), and a three-dimensional
forward-looking conical image is constructed (step 13C50).
[0092] The angle of the scanning assembly with respect to the
central axis of the imaging device may be adjustable within a range
of .about.0.degree. to .about.180.degree.. More particularly, the
angle of the scanning assembly with respect to the central axis of
the imaging device may be adjustable within a range of
.about.60.degree. to .about.120.degree.. Further, step 13C20 may be
performed continuously during step 13C30. Furthermore, steps
13C20-13C30 may be configured to produce a spiral scan.
[0093] In each of the above discussed embodiments, the scanning
assembly is shown to include one transducer. However, large ranges
of motions may be difficult to achieve with only one transducer.
The required range of motion may be cut in half by using, for
example, two transducers, as shown in FIG. 11A-11C. In the
exemplary embodiment shown in FIG. 11A-11B, the scanning assembly
1166 includes two transducers 1134a and 1134b, which may be placed
at half of the sector angles and alternately fired to generate scan
lines.
[0094] Further, in certain cases it may be beneficial to scan,
instead of one conical forward-looking image, two or more conical
forward looking images, where such information may be advantageous.
FIG. 11C shows an embodiment in which two transducers are provided.
In the embodiment of FIG. 11C, the two transducers are positioned
at different angles about the central longitudinal axis of the
scanning assembly. The two transducers may be operated at different
scanning frequencies to image different tissue types or structures.
In FIGS. 11A-11C, two transducers are shown; however, more than two
transducers may be utilized to produce proportional results.
[0095] The following references are incorporated herein by
reference for the teachings they provide:
TABLE-US-00001 US Patent/Appl # Inventor Filing Date Patent Date
11/053,141 Magnin et. al. Feb. 8, 2005 Display apppl. Magnin et.
al. Mar. 6, 2006 6860855 Shelby et. al. Nov. 19, 2001 Mar. 1, 2005
6960172 McGurkin et. al. Aug. 15, 2003 Nov. 1, 2005 6445939 Swanson
et. al. Aug. 9, 1999 Sep. 3, 2002 7025765 Balbierz et. al. Mar. 30,
2001 Apr. 11, 2006 7022082 Sonek et. al. May 13, 2002 Apr. 4, 2006
6863676 Lee et. al. Jan. 31, 2002 Mar. 8, 2005 6095981 McGahan Jul.
1, 1998 Aug. 1, 2000 5469853 Law et. al. Jun. 22, 1994 Nov. 28,
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[0096] Research Laboratory of Electronics at MIT Optical
Devices--Laser Medicine and Medical Imaging Group Progress Report
143 Chapter 11 [0097] Research Laboratory of Electronics at MIT
Photonic Materials, Devices and Systems--Laser Medicine and Medical
Imaging Group Progress Report 144 Chapter 27
[0098] Any reference in this specification to "one embodiment," "an
embodiment," "example embodiment," etc., means that a particular
feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the
invention. The appearances of such phrases in various places in the
specification are not necessarily all referring to the same
embodiment. Further, when a particular feature, structure, or
characteristic is described in connection with any embodiment, it
is submitted that it is within the purview of one skilled in the
art to effect such feature, structure, or characteristic in
connection with other ones of the embodiments.
[0099] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this invention. More particularly, reasonable
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the foregoing disclosure, the drawings and the
appended claims without departing from the spirit of the
disclosure. In addition to variations and modifications in the
component parts and/or arrangements, alternative uses will also be
apparent to those skilled in the art.
* * * * *